Relatively little is known about how important individual difference orientations affect processes of relationship initiation, development, and deterioration. Recently, the PI has developed a construct and self-report inventory that assesses one such important individual difference dimension- -the orientation individuals adopt toward engaging in casual and uncommitted sexual relations with romantic partners. The broad objectives of this proposal are two fold: 1) to conduct two studies designed to provide initial convergent and discriminant validity evidence for this new inventory; and 2) to extend the construct validation process by conducting a series of four studies designed to clarify how individual differences on this dimension affect processes underlying relationship initiation, maintenance, and termination. Once construct validity evidence has been provided for the Inventory, the PI eventually intends to study whether, how, and why individual differences in orientation to sexual relations influence the incidence of marital instability (e.g., divorce), the processes and paths by which marriages dissolve, and the psychological, emotional, and health related consequences of divorce on individuals' well-being.